Sound box of sound-reproducing machines



Patented lt/laro 22S,

Uhllll@ Lemon FRANK MLTON W'INTER, OF WELLINGTON, NEW ZEALA'HD.

SOUND BOX or seUnn-nnraonncrne Macnrnns.

Application filed August 2', 1924. Serial No. 729,829.v

To @ZZ whom z'' may conce/ra:

Be it known that Farine; Miur-N lli/Trierer, citizen of the Dominion of New Zealand, residing at Seaside rlheatre, Lyall Bay, TNellington, in the Provincial District of fileliington, has invented certain new and useful improvements in Sound Boxes of Soundleproducinp` lilachines, of which the following' is a specification.

rl`his invention relates to sound boxes or reproducers, used on gramophones and otherl machines for the purpose of reproducing the human Voice, musical and other sounds.

' The object of the invention is to provide improvements whereby such sounds may be reproduced in a better manner than hereto fore.

The improvements are directed to that type of sound box or reproducer, wherein is fitted a diaphragm having attached thereto one end of a stylus bar, said improvements consisting` first-ly in the employment of a metal diaphragm of the nature of aluminium or copper in conjunction with a washer of either Vulcanite or mica or material of a similar nature, and secondly the special method of securing the stylus bar to the diaphragm, and thirdly in the means by which the Volume of sound can be in creased or decreased by varying the depth of the washer or by flexing the diaphragm to decrease or increase respectivelythe air space between the diaphragm and. the back of the sound box or reproducer.

The improvements will be further described in conjunction with the accompanying,- drawing wherein Figure 1 is a vertical sectional View and Figure 2 a front View of a sound box or reproducer, fitted with the improvements, while Figure 3 is a detail View illustrating` the attachment of the stylus bar to the diaphragm and Figure t is a vertical sectional View illustrating a modilication.

In the drawing 1 is the' frame of the sound box or reprodueer, and has secured thereto by screws 2 the usual back plate 3, the latter containing a central hole 3.a.

A washer i of rubber and a tube 5 the inner diameter of each of which is the same as that of the hole 3a, are .secured to the back plate 3 by bolts 6 `passing,` through the latter, the rubber washer 4l and the flange of a@ ab@ a Y The diaphragm 7 which is nietal of the nature of aluminium or copper7 preferably the former material, is lgrip ed at its edge etween rubber rings 8 he d between 'the back plate 3 and the flange 1 of the sound boxer reproducer.

The stylus bar 9 is mounted on the frame 1 in any known manner preferably by having a screw 10 passed tl'ierethrough and entered in the frame, a spring 11 on said screw benreen the head thereof and the stylus bar 9 keeping the latter pressed against pointed projections 12 from the frame 1.

lhe upper end of the stylus bar 9 is ate tached to the diaphragm 7 by a screw 18 of metal or 'yulcanitm said screw passing througli a washer 1+i of vulcanite, niicaor material of a similar nature and preferably hollow, placed with its hollow side against the back of the diaphragm 7? the central hole in the latter through which the screw 13 passes being` of greater diameter than said screw so that the diaphragm does not contact therewith.

ln the preferred form the diaphragm 7 is gripped between either the heel or the toeportion only of the upper end 9 of the stylus bar 9 and the washer 14;, although said end 9 can be made to bridge the hole 15 and cause the diaphragm Z to be gripped at opposite sides of the hole 15 between the washer 1li and end portion 9 of the stylus bar 9.

rllhe volunie of sound reproduced can be decreased or increased by increasing' or de-` creasing` respectively the depth of the washer let, this method of controlling the volume of sound beingJr adopted where a con'iparatively thick diaphragm 7 is employed, as shown in Figure el.

A further method of controlling the volume of sound is to dish the diaphragm 7 so as to decrease or increase the air space 16 between the diaphragm 7 and the back plate 5, decreasing' said air space by flexing the diaphragm 7 towards the back plate resulting; in a greater Volume of sound being` reproduced, while dishina` or flexing the diaphragm from the bach plate 3 results in a decrease in the volume of sound.

lli/Then a dished diaphragm 7 is employed, it is preferably flexible enough to permit it to be Clished by the application of pressure to the diaphragm or by gripping and pulling the stylus bar 9, while the diaphragm is held ia f1.1@ freie@ It desired the roliime of sound can be further controlled where the dished diaphragm is used, by varying' the depth of the washer lll as before described.

A sound box or reproducer fitted with a metal diaphragm is enabled to Stand harder wear and tear than a sound box or reproducer fitted with a mica diaphragm7 besides which the Volume of Sound reproduced controllable bv varying' the depth out the washer, or by dishiug' the diaphragm,

or by both means.

` l'hat l do claim :md desire to obtain by Letters Patent of the United States of Auierieapir- 1. In a sound box or reproducer of the type speeiied, the combination with a metal dii-iphragm, or' a Stylus bar located on one side of said diaphrae'mr` a hollow non-metallic cup-shaped washer on the opposite side o't the diaphragm with the rim of the Cup- Shaped washer bearing against the diaphrapgm, and a screw between the cup-shaped `waeher and the stylus bar securing the parte together.

2. In a sound box or reprodueer of the type speeiiiech the combination with a metal diaphragm provided with an opening", of a stylus bar located on (me side of said diaphragm, a hollow cup-shaped washer on the opposite side of the diaphragm, and a screw of' smaller diameter than the opening` in the diaphragm passing through the washer and opening but out of Contact therewith, and entering`- the upper end ol the stylus bar for clamping' the diaphragm between the washer and the upper end of the Stylus bar.

3. In a sound box or reproducer olf the type specified, the combination with a. metal diaphragm provided with au opening, of a sty/lus bar located on one side of said diaphragm, a non-metallic hollow cup-shaped washer located on the opposite side of the 'diaphragm with the rim bearing` against the diaphragm and surrounding the opening therein, and a screw of smaller diameter than the opening in the diaphragm passing' through the washer and opening but out of Contact therewith. and enterirre` the upper end of the stylus bar for clamping the diaphramu between the washer and the upper cud of' the stylus bar.

In testimony whereof I have signed my name to this Specific-ation.

FRANK MILTON VINTER, 

